Below, get a sneak peek into Friday's episode of Syfy's Merlin entitled 'The Disir'. In the episode, when three soothsayers cast a dark curse upon Arthur in the depths of an ancient pool. The episode airs Friday at 10/9c.

The fourth season finds Camelot on the brink of a Golden Age of magic, mystery and action-adventure. With Morgana now a dangerous outcast, Merlin must use all his powers to ensure Arthur fulfills his destiny as the Once and Future King. Colin Morgan returns as Merlin alongside Bradley James as Prince Arthur, Angel Coulby as Gwen and Katie McGrath as Morgana. Anthony Head reprises his role as King Uther and Richard Wilson as Gaius.

The show is produced and created by the award winning team at Shine TV. FME holds the exclusive distribution, home entertainment and licensing rights to "Merlin" (known as "The Adventures of Merlin" in the rest of the world outside the US and UK) and has sold the series to over 52 broadcasters in more than 180 countries including Network Ten in Australia, MICO in Japan and RTL in Germany.